For well-preserved vocals in captivity, I reached for Mayte Martín's Tempo Rubato album with "Música de mi locura" to combine female Flamenco-styled voice with string quartet, Spanish guitar and cajon.

• ElectroHarmonix 300B: by now disqualified as not belonging into the same league – a fine all'rounder and starter pack but incapable of revealing this machine's true potential
• Elrog 50: once again quickest, most direct and lit up, hence more forward on energetic perspective but on spaciousness just a bit 'hallucinante' as my old Peruvian friend Nino used to put it
• Western Electric 300B: if the ER50 was a spicier perfume containing lemon grass and ginger, the WE's aroma was a bit heavier and sweeter to bleed into my subjective perception of tempo which here was a touch more languid

My takeaway from this exploratory session was that 1/, the Elrog and Western Electric were far more advanced than the stock valve which shouldn't come as a shock. Their tarrifs are that much steeper. 2/, Dan had been very crafty in his sample selection to give me two distinct flavors. For top speed, the higher adrenaline rush of quasi 'live' frisson and something slightly spooky about 3D staging, the German 50 from Elrog had it. For a more relaxed and weightier read of more burnished colors, albeit without at all inserting that keep-at-bay curtain which the ElectroHarmonic pulled (down), the Western Electric did. The Elrog was twitchy like a fish wiggling mad in your hands. The WE was wonderfully liquid hence more relaxed. Put in mix'n'match terms, I'd mate the WE with our quicker class A/B ultra-bandwidth LinnenberG Liszt and the Elrog with our class A Pass amp if I wanted dovetailing. If I wanted like+like enhancement, I'd mate the WE with the Pass and Elrog with LinnenberG.

With Elrog ER50

With 'lighter than air' membranes mere inches off the ear drums, planar headfi in these leagues is about as direct as it gets already, Raal Requisite SR1a floating-baffle ribbons excepted which operate at an even higher level of speed and dynamic verve. I thus found the Elrog nearly too intense. Also, its lower gain meant that on Susvara, I had little headroom for albums mastered lower to retain higher dynamic range. As such I preferred the Western Electric which in this context was still unbelievably finger-in-the-socket electrifying, just not quite as charged. This was probably as direct-coupled as tubes can get not just circuit but ear wise. Forget background listening unless you dial back the volume to very faint. Powered by L2, headphone listening with planars as quick as these HifiMan is a full-contact game. That means exhausting not in any bad sense of distortion or brightness fatigue but in the sheer amount of attention it commands. Such sensory intensity is sustainable only for a certain amount of time before one needs a break.

Damn! Tube rolling at this level was deliciously shifty business. And already in-bound was the pair of KR-built Living Voice 300B modeled on the Western Electric. With a pair of originals on hand, this would be interesting. Sasa Cokic of Trafomatic fame meanwhile calls out his favorite 300B as the Emission Labs true mesh plate. He offered to have a pair sent to Ireland. I was also curious how my take on his tubes, in our room and system, would track Dan's own, in his room and system. Next I rejigged my headfi setup to hear the Raal with WE and Elrog exotica. With a sample Purifi amp still on hand—this is the latest "beyond Ncore" tech from a Danish joint venture wherein Bruno Putzeys and Lars Risbo handle next-gen class D circuit design and math—I had an ideal high-power no-noise driver of very high resolution for the ribbons. Raal's interface box between Purifi amp and floating-baffle ear speakers presented the amp with a benign stable 6Ω not the virtual dead short of the ribbons proper. This combined retro tech of direct-heated triodes with FutureFi of cutting-edge class D aimed at the OEM market. NAD became the first Purifi licensee at Munich's show this year. Others will undoubtedly follow.

Now playing at the absolute apex of resolution and bandwidth our household was capable of, I could listen to Hiwa Tawaji's "La chou ta etham" which recalls big Las Vegas spectacles from her 30-track 30 album and hear things the YouTube stream on my desktop was a most pale imitation of despite using a fully balanced COS Engineering H1 headfi/DAC to drive Final's D8000 planars on custom silver cabling. The key point to be made for the Elrog and Western Electric? In such an ideal(ized) setting, both exhibited extension, speed and detail magnification that was shocking and will be impossible to recreate with loudspeakers. Room interference, crossover interference, phase shift, box resonances and copious reflections inside and outside the enclosures all lower their yard stick significantly. Unless you had a Berning ZOTL amplifier, you'll never even hear the exploded treble which these DHT own when properly tapped. Typical output transformer limitations just won't allow it. Feeding ribbon headphones with grounded-grid DHT thus worked in an alternate reality. At SPL equivalent to what I'd used on Susvara, the impression of sensory pressure as an onslaught of crystalline detail perfectly separated thus individualized was even more intense. I felt like the proverbial kid in the candy store. He doesn't know where to look first. The variety on offer is too overwhelming.

That fact was the overriding overlap between Elrog 50 and WE 300B. Whilst I could still make out a slightly leaner more quicksilvery tendency for the German tube, that signature was utterly dominated by what both did to equal degrees: present packed detail density seemingly resolved down to a tune's very bones. The upshot was that my ability to perceive everything had been temporarily enhanced. If I listened at regular levels to fare of the Hiba track's studio trickery—where hearing everything is a lot—I was good for about 20 minutes. Then I needed time out. That was spectacular and humbling all at once. Of course I could simply turn the volume down and dilute intensity. That's exactly what I'd do for longer sessions. But the point is made. If you thought tubes operate at lower bandwidth and resolving power than transistors, this particular setup would have completely overwritten and rebooted your notions. For some reason, I'd not anticipated being this impressed and surprised when I asked Vinnie to install the optional headphone outputs. Now I was thrilled to bits that I had. If you see an L2 Signature Preamplifier in your future, you'd cheat yourself very badly indeed if you failed to order at least one of the headphone sockets.

In fact, so successful is the L2 at this statement headfi job that one could hope for an eventual L2i integrated where a dedicated 5-watt headphone amp replaced the big 100-watt speaker amp but retained the preceding 6SN7 gain stage. This would be a lower-tier option to doing DHT headfi over the L2 Signature preamp. As to the XLR vs. the RCA|¼" outputs, "the harmonic distortion content from the balanced circuitry (0.0005% at 1kHz) is orders of magnitude lower than that of the DHT stage. The THD of the triodes completely dominates so on that note, the balanced and single-ended outputs are pretty much identical."